From e2e6bc81f034b6c10f0b069e8f255e4b528c71a4 Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Wed, 11 Jan 2012 11:20:30 +0100
Subject: [PATCH] --- yaml --- r: 297062 b: refs/heads/master c:
 b9e5dc8d4511e6a00862a795319569e7fe7f60f4 h: refs/heads/master v: v3

---
 [refs]                                  |  2 +-
 trunk/Documentation/virtual/kvm/api.txt | 23 +++++++++++++++++++++++
 trunk/arch/ia64/include/asm/kvm.h       |  4 ++++
 trunk/arch/powerpc/include/asm/kvm.h    |  4 ++++
 trunk/arch/s390/include/asm/kvm.h       |  3 +++
 trunk/arch/x86/include/asm/kvm.h        |  4 ++++
 trunk/include/linux/kvm.h               | 15 +++++++++++++++
 7 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index fe5d6bd1f25e..fc082e8ef4cb 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8d26cf7b40b1648c39e77a113dac07ad31363120
+refs/heads/master: b9e5dc8d4511e6a00862a795319569e7fe7f60f4
diff --git a/trunk/Documentation/virtual/kvm/api.txt b/trunk/Documentation/virtual/kvm/api.txt
index a67fb35993fa..7ca696227d3a 100644
--- a/trunk/Documentation/virtual/kvm/api.txt
+++ b/trunk/Documentation/virtual/kvm/api.txt
@@ -1771,6 +1771,29 @@ developer registration required to access it).
 		/* Fix the size of the union. */
 		char padding[256];
 	};
+
+	/*
+	 * shared registers between kvm and userspace.
+	 * kvm_valid_regs specifies the register classes set by the host
+	 * kvm_dirty_regs specified the register classes dirtied by userspace
+	 * struct kvm_sync_regs is architecture specific, as well as the
+	 * bits for kvm_valid_regs and kvm_dirty_regs
+	 */
+	__u64 kvm_valid_regs;
+	__u64 kvm_dirty_regs;
+	union {
+		struct kvm_sync_regs regs;
+		char padding[1024];
+	} s;
+
+If KVM_CAP_SYNC_REGS is defined, these fields allow userspace to access
+certain guest registers without having to call SET/GET_*REGS. Thus we can
+avoid some system call overhead if userspace has to handle the exit.
+Userspace can query the validity of the structure by checking
+kvm_valid_regs for specific bits. These bits are architecture specific
+and usually define the validity of a groups of registers. (e.g. one bit
+ for general purpose registers)
+
 };
 
 6. Capabilities that can be enabled
diff --git a/trunk/arch/ia64/include/asm/kvm.h b/trunk/arch/ia64/include/asm/kvm.h
index bc90c75adf67..b9f82c84f093 100644
--- a/trunk/arch/ia64/include/asm/kvm.h
+++ b/trunk/arch/ia64/include/asm/kvm.h
@@ -261,4 +261,8 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
 #endif
diff --git a/trunk/arch/powerpc/include/asm/kvm.h b/trunk/arch/powerpc/include/asm/kvm.h
index f7727d91ac6b..7d9d4de057ef 100644
--- a/trunk/arch/powerpc/include/asm/kvm.h
+++ b/trunk/arch/powerpc/include/asm/kvm.h
@@ -265,6 +265,10 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
 #define KVM_REG_MASK		0x001f
 #define KVM_REG_EXT_MASK	0xffe0
 #define KVM_REG_GPR		0x0000
diff --git a/trunk/arch/s390/include/asm/kvm.h b/trunk/arch/s390/include/asm/kvm.h
index 82b32a100c7d..325560afb77e 100644
--- a/trunk/arch/s390/include/asm/kvm.h
+++ b/trunk/arch/s390/include/asm/kvm.h
@@ -41,4 +41,7 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
 #endif
diff --git a/trunk/arch/x86/include/asm/kvm.h b/trunk/arch/x86/include/asm/kvm.h
index 4d8dcbdfc120..e7d1c194d272 100644
--- a/trunk/arch/x86/include/asm/kvm.h
+++ b/trunk/arch/x86/include/asm/kvm.h
@@ -321,4 +321,8 @@ struct kvm_xcrs {
 	__u64 padding[16];
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
 #endif /* _ASM_X86_KVM_H */
diff --git a/trunk/include/linux/kvm.h b/trunk/include/linux/kvm.h
index 6cf048d9604b..245bcb3a0fcd 100644
--- a/trunk/include/linux/kvm.h
+++ b/trunk/include/linux/kvm.h
@@ -279,6 +279,20 @@ struct kvm_run {
 		/* Fix the size of the union. */
 		char padding[256];
 	};
+
+	/*
+	 * shared registers between kvm and userspace.
+	 * kvm_valid_regs specifies the register classes set by the host
+	 * kvm_dirty_regs specified the register classes dirtied by userspace
+	 * struct kvm_sync_regs is architecture specific, as well as the
+	 * bits for kvm_valid_regs and kvm_dirty_regs
+	 */
+	__u64 kvm_valid_regs;
+	__u64 kvm_dirty_regs;
+	union {
+		struct kvm_sync_regs regs;
+		char padding[1024];
+	} s;
 };
 
 /* for KVM_REGISTER_COALESCED_MMIO / KVM_UNREGISTER_COALESCED_MMIO */
@@ -570,6 +584,7 @@ struct kvm_ppc_pvinfo {
 #define KVM_CAP_S390_GMAP 71
 #define KVM_CAP_TSC_DEADLINE_TIMER 72
 #define KVM_CAP_S390_UCONTROL 73
+#define KVM_CAP_SYNC_REGS 74
 
 #ifdef KVM_CAP_IRQ_ROUTING